Backhoe bucket construction



A ril 30, 1968 A. H. LEESE 3,

. BACKHOB BUCKET CONSTRUCTION Filed July 28, 1966 A I s Sheets-Sheet 1FIG.2

INVENTOR ATTORNEV 4 April 1968 A. H. LEESE 3,380,604

BACKHOE BUCKET CONSTRUCTION Filed July 28, 1966 3 Sheets-Sheet 2 INVENTOR A 7' TORNEV A. H. LEESE April 30, 1968 BACKHOE BUCKET CONSTRUCTION 5Sheets-Sheet Filed July 28, 1966 F l G 5 lNl/EN TOR ATTORNEY UnitedStates Patent 3,380,604 BACKHOE BUCKET CONSTRUCTION Aihert H. Leese,Rochester, Mich, assignor to Ford Motor Company, Dearborn, Mich acorporation of Delaware Filed July 28, 1966, Ser. No. 568,557 Claims.(Cl. 214138) ABSTRACT OF THE DISCLOSURE -A backhoe bucket is providedwith an ejector which also serves to mount the bucket on the end of adipstick for articulation about a pair of parallel axe-s. Upon movingthe bucket to dump position, the weight of the bucket and content causesthe bucket to drop slightly, rotating the ejector to force material fromthe bucket.

This invention relates to backhoes and more particularly to ejectorbuckets for backhoes.

Backhoe buckets sometimes are provided with ejectors to aid in dumpinthe contents. Ejectors are of particular utility in digging clay andmore sticky soils by use of relatively narrow buckets, in which thematerial tends to cling to the walls of the bucket instead of dumpingwhen the bucket is inverted. Ejectors, which usually are power operated,comprise a member extending between the bucket sides and swingable aboutan axis at a corner of the bucket to sweep the bucket from rear to frontupon dumping to dislodge any material tending to adhere to the bucketwalls.

The ejector of the present invention is operated by the weight of thebucket and contents, which tend to force the ejector forwardly to sweepthe interior of the bucket. This is accomplished by articulating thebucket on the end of the dipstick by a short link comprising an integralportion of the ejector. When the dipstick and bucket are positioned todump the contents of the bucket, the weight of the bucket and contentsserves to rotate the ejector about its connection to the end of thedipstick and thereby rotate it with respect to the dipstick and bucketand force it forwardly to sweep the volume of the bucket and dislodgeany dirt tending to stick within the bucket.

Among the objects of the present invention are to provide an improvedejector for backhoe buckets which is operated by the weight of thebucket and its contents; to provide such a construction in which theejector does not interfere with the digging cycle of the backhoe; toprovide such a construction which is simple and durable;

and generally to improve constructions of the type described.

Other objects, and objects relating to details and economies ofconstruction will be more apparent from the detailed description tofollow.

My invention is clearly defined in the appended claims. In the claims,as well as in the description, parts may at times be identified byspecific names for clarity and convenience, but such nomenclature is tobe understood as having the broadest meaning consistent with the contextand with the concept of my invention as distinguished from the pertinentprior art. The best form in which I have contemplated applying myinvention is illustrated in the accompanying drawings forming a part ofthis specification in which:

FIGURE 1 is a somewhat diagrammatic side elevation of a backhoe, showingthe bucket and dipstick in position to commence the digging cycle. Therear portion of the tractor is shown.

FIGURE 2 is a side elevation similar to FIGURE 1, the digging cyclehaving been commenced.

FIGURE 3 is a side elevation similar to FIGURE 1, the boom and dipstickbeing positioned for dumping and the bucket till being closed.

FIGURE 4 is a view similar to FIGURE 3, the bucket being shown in open,dump position.

FIGURE 5 is an enlarged vertical cross section of the bucket taken alongthe line 5-5 of FIGURE 6, the ejector and portions of the dipstick andbucket operating linkage being shown in side elevation.

FIGURE 6 is a transverse section of the bucket, ejector and dipstick,taken generally along the line 66 of FIGURE 5.

FIGURE 7 is a fragmentary vertical section of the bucket, showingdetails of construction.

Referring now to the drawings, the backhoe to which the ejector bucketconstruction of the present invention is applied is more or lessconventional, comprising a boom 10 which is pivotally mounted forvertical swinging movement on a swing frame 11 mounted for horizontalswinging movement on a main frame 12 mounted on a tractor 14. A dipstick15 is pivotally mounted for vertical swinging movement on the outer endportion of the boom 10 and a bucket 16 is mounted for vertical swingingmovement on the outer end of the dipstick 15.

A boom lift cylinder 17 extends between the swing frame 11 and a portionof the boom 19 to raise and lower the boom. A crowd cylinder 19 extendsbetween a portion of the boom and the dipstick 15 to swing the dipstickabout its pivotal connection on the boom. A bucket cylinder 20 extendsbetween a portion of the dipstick 15 and a linkage 21 consisting of aportion of a four-bar linkage 21 for swinging the bucket 16 about itspivotal connection on the dipstick. All of these cylinders aredouble-acting hydraulic cylinders and are controlled by a bank ofhydraulic control valves contained within a control console 22positioned adjacent an operators seat 24 on the tractor 14.

In operation, the boom 10 and dipstick 15 are extended as indicated inFIGURE 1 to commence the digging stroke. Then by swinging the dipsticktowards the operator (crowding), the bucket 16 is engaged with theground for the digging stroke. As the digging stroke progresses, thebucket cylinder 20 may be operated to swing the bucket towards theoperator (close the bucket) in order to relieve any overload in thehydraulic circuitry to the crowd cylinder 19. If curling the bucket doesnot relieve the overload, as evidenced by continued blowing of apressure relief valve (not shown), the lift cylinder 17 may be actuatedto lift the boom slightly and relieve the overload.

As the bucket 16 is being filled, it is rotated to closed position asindicated generally in FIGURE 3. When the bucket is filled, the liftcylinder 17 is actuated to lift the dipstick 15 and bucket from theexcavation, the boom 10, dipstick and bucket being generally in theposition indicated in FIGURE 3, after which the backhoe may be swung toone side or the other of the excavation and the bucket rotated away fromthe operator (opened) to dump the contents of the bucket, after whichthe digging stroke is again repeated. The backhoe construction andoperation described immediately above are conventional.

When digging clay and other sticky soils, particularly when using arelatively narrow width bucket, difficulty often i encountered with dirtfailing to drop from the bucket when the bucket is opened for dumping,as in FIGURE 4. According to the present invention, an ejector 25 ispivoted to sweep the volume of the bucket as the bucket is opened andpush before it any dirt tending to adhere to the inner surfaces of thebucket. The ejector and bucket will now be described in detail.

The bucket 16 comprises a pair of side walls 2-6 and 27 connected by anarcuate bottom wall 29. The bottom wall 29 preferably lies along an arcextending about a bucket axis 39 as a center. Cutting lips 31 and 32 areprovided along the leading edge of the bucket side walls 25 and 27, andbucket teeth 34 are provided along the leading edge of the bottom wall29. The side walls 26 and 27 of the bucket are connected by cross braces35 and 36 at the rear of the bucket.

An ejector 37 is mounted for swinging movement on the bucket axis 39,which is located adjacent the upper front corner of the bucket 16. Theejector 37 extends between the side walls 26 and 27 of the bucket so asto sweep the volume of the bucket and may comprise a relatively flatplate spanning between the bucket walls or a V-shaped member lyingadjacent the bucket walls, as is well known in the art. The braces 35and 35 limit rearward swinging movement of the ejector 37 and theejector when in rearward position forms the rear wall of the bucket (seeFIGURE When swung forwardly, the ejector 37 lies generally along thefront edge of the bucket.

The ejector 37 is provided with a projecting portion 39 extending fromthe top of the bucket when the ejector is swung rearwardly (see FIGURE5). The portion 39 is provided with a horizontal transverse axis 40 formounting the ejector for pivotal movement on the end of the dipstick 15.The ejector axis 40 and the bucket axis 30 are relatively closely spacedand the projecting portion 39 of the ejector provides a short linkwhereby the bucket 16 is articulated for vertical swinging movementabout the outer end of the dipstick 15. In the form shown, a planepassed through the axes 30 and 4!) lies at an angle approaching theperpendicular to the general plane of the ejector 37. This angle and thedistance between the axes 30 and 40 may be varied if desired to increaseor decrease the force available for swinging the ejector 37 forwardlyduring the dumping operation.

The bucket cylinder operating through the bucket operating linkage 21,which is pivoted to the outer portion of the dipstick and to the bucket16, serves to swing the bucket in a vertical plane about the axes 30 and40. The links 21, the portions of the bucket and dipstick between theattaching points of the linkage 21 and the axes 30 and 40, respectively,and the projecting portion 39 of the ejector between the axes form afive-bar bucket operating linkage for articulating the bucket on the endof the dipstick and swinging it vertically. This operating linkage isunstable, and when the bucket is positioned for digging as shown inFIGURE 1, the ejector will be swing forwardly within the bucket, theejector axle 40 resting against pads 41 on the upper edge of the bucketside wall 26 and 27. Upon engagement of the bucket with the ground asindicated in FIGURE 2, the reaction to the digging effort will tend tocause the bucket to rise relative to the dipstick, swinging the ejector25 to he reart of the bucket where it will remain during the rest of thedigging cycle and while the bucket is maintained in a closed positionand the backhoe swung for dumping (see FIGURE 3). Upon the bucket beingmoved to open position by operation of the cylinder 20, the combinedweight of the bucket 16, ejector 25 and bucket contents will tend todrop the bucket relative to the end of the dipstick 15, the bucket axis39 moving to a position generally beneath the ejector axis 40 andswinging the ejector 25 forwardly to sweep the volume of the bucket anddislodge any dirt tending to adhere to the side walls of the bucket.

The bucket and ejector of the present invention permit the use of narrowbuckets for digging in sticky soils and make it unnecessary to provideadditional linkage or cylinders for swinging the ejector, except inunusual operating conditions. Further, the present invention is suitablefor use with the conventional backhoe by substitution only of theejector and the bucket. When the ejector is not required, it does notsubstantially interfere with operation of the backhoe in normal digging,although the ejector may easily be removed and the bucket mounteddirectly on the dipstick in the usual manner.

What is claimed is:

1. In a backhoe, a dipstick, a bucket articulated on the outer end ofthe dipstick for oscillation about first and second closely spaced,horizontal, transverse axes, a double-acting hydraulic cylinderconnected with the bucket and the dipstick for rotating the bucket aboutits axes, the bucket having opposite sides and an arcuate bottom, and anejector swingably mounted on the first transverse axis for swingingmovement between the front and rear of the bucket and having a portionextending between the bucket sides so as to sweep the volume of thebucket, the ejector having a projecting portion linking the bucket tothe end of the dipstick and provided with said second transversehorizontal axis parallel to and located a short distance from the axismounting the ejector on the bucket and forming a common axis forrotation of the bucket and ejector about the end of the dipstick, theweight of the bucket and contents when in bucket clumping positiontending to rotate the ejector about the second transverse axis in adirection to lower the bucket and cause the ejector to sweep the volumeof the bucket due to downward arcuate movement of the first transverseaxis about the second axis as a center.

2. In a backhoe construction as claimed in claim 1, the first transverseaxis being located at the upper front corner of the bucket.

3. In a backhoe construction as claimed in claim 2, the arcuate bottomof the bucket being generally concentric with the first transverse axis.

4. In a backhoe construction as claimed in claim 1, the first and secondtransverse axes for mounting the bucket 0n the dipstick lying in a planemaking a angle approaching with the general plane of the ejector.

5. In a backhoe construction as claimed in claim 1, the hydrauliccylinder being connected with the bucket and dipstick by a pair of linksextending from a common point at the connection of the links to thecylinder.

References Cited UNITED STATES PATENTS 2,812,872 11/1957 Perkins et al.214-138 X FOREIGN PATENTS 883,969 12/1961 Great Britain.

HUGO O. SCHULZ, Primary Examiner.

